TREAT allows calculating average non-HVAC (base) load and heating slope (building heat loss rate) by analyzing utility bills with daily outdoor temperatures during the billing periods. You may choose to obtain utility bills and run billing analysis before going to a site visit to get a better idea about the energy performance of the building. Billing analysis is also a valuable tool for validating the building energy model by comparing the modeled results to actual billing information.
As with any statistical calculations, it is important to have large amount of reliable billing data available in order to get meaningful results. We recommend that you have at least twelve actual utility bills available for each analyzed fuel. If a fuel is used for both base and HVAC load, then the bills must be available for the months without noticeable heating and/or cooling.
TREAT normalizes billing data based on the calculated heating and cooling degree days per time period, it does not perform regression analysis of the bills. The user has to specify heating and cooling reference temperatures if billing analysis is run independently from the building model; in TREAT v 3.4 a reference temperature of 65° F is available. In this case the accuracy of the billing analysis strongly depends on the reliability of the assumptions.
To run billing analysis, fill out the screens in the Billing Data section. Skip the Metered Spaces screen for projects where usage of each fuel is measured by a single meter. See the Billing Data section for more details.